Some people hurt themselves, while others hurt those around them. Both are human responses. And if it's human, perhaps it can be cured. Dr. Park Seonghwa was certain of this truth. As a psychotherapist, he believed he could observe Hongjoong, a criminal convicted of multiple murders, without becoming entangled. But curiosity carries a price. When Seonghwa hesitates, pulling back, Hongjoong feels used, and escapes custody, hunting him down. What follows is a descent into hell: captivity, manipulation, and brutal games of control, where Seonghwa's own mind becomes the battlefield. He soon discovers that understanding a monster may mean becoming one yourself. And through it all, one question remains: is this connection salvation, or the destruction of them both?